NEW YORK (Reuters) - Generic drugmaker Perrigo Co. is recalling 11 million bottles of over-the-counter pain killer acetaminophen caplets after finding metal fragments in some batches, U.S. health officials said on Thursday.

The 500-milligram pills sold as store brands may have been sent to dozens of outlets around the United States, including some owned by Wal-Mart, Safeway, CVS and Food Lion, the U.S. Food and Drug Administration (FDA) said.